They were two of the guests of honour at one of the most historic of royal weddings but they were still stopped in their tracks as they attempted to pop outside for a quick smoke.

Tom Parker Bowles and his sister, Laura, were in the middle of the celebrations marking the marriage of their mother, Queen Camilla, to Charles III when they decided they wouldn’t mind a cheeky cigarette break.

However, as they snuck through the corridors of Windsor Castle, a rather familiar voice brought a halt to their adventure.

Queen Elizabeth II was right behind them and asked ”are you lost?”

The anecdote has been recounted by Tom Parker Bowles in an interview with the Daily Telegraph. He told the paper he only met the late Queen twice in his life. The first time, he was still a small child and got so confused that he curtseyed to her. The second occasion was at the marriage of Charles and Camilla who wed legally at Windsor Guildhall and then had a religious blessing at St. George’s Chapel followed by a reception at Windsor Castle.

Queen Elizabeth II didn’t attend the civil marriage ceremony, the first time an heir to the throne had wed outside of church law, but she was present at the blessing and the party, delivering a famously witty and warm speech to welcome her new daughter-in-law to the Royal Family.

However, she seemed less keen on the bride’s two adult children sneaking out of the reception. Tom Parker Bowles doesn’t reveal what happened next but the tone of the question implies Elizabeth II may not have been entirely amused by the idea.

King Charles and Queen Camilla married on April 9th 2005. They will celebrate their twentieth wedding anniversary while on a State Visit to Italy.